Polarizer Nanoimprint Lithography

ABSTRACT

A method of making a polarizer can include applying a liquid with solid inorganic nanoparticles dispersed throughout a continuous phase, then forming this into a different phase including a solid, interconnecting network of the inorganic nanoparticles. This method can improve manufacturability and reducing manufacturing cost. This method can be used to provide an antireflective coating, to provide a protective coating on polarization structures, to provide thin films for optical properties, or to form the polarization structures themselves.

CLAIM OF PRIORITY

This application claims priority to U.S. Provisional Patent ApplicationNo. 62/656,759, filed on Apr. 12, 2018, which is incorporated herein byreference.

FIELD OF THE INVENTION

The present application is related generally to polarizers.

BACKGROUND

A polarizer can divide light into two different polarization states. Onepolarization state can pass through the polarizer and the other can beabsorbed or reflected. The effectiveness or performance of polarizers isbased on a very high percent transmission of one polarization (e.g. Tp)and minimal transmission of an opposite polarization (e.g. Ts). It canalso be beneficial to have high contrast (e.g. Tp/Ts). Contrast can beimproved by increasing transmission of the predominantly-transmittedpolarization (e.g. increasing Tp) and by decreasing transmission of theopposite polarization (e.g. decreasing Ts).

A polarizer can be used in an application with high temperatures, suchas for example projectors. As projectors decrease in size and increasein brightness due to customer demand, the need for polarizers that canendure a high temperature environment also increases.Selectively-absorptive polarizers are particularly susceptible to damagein high-light-intensity projectors because they absorb a large percentof incident light. Such polarizers typically have wires that include areflective portion (e.g. aluminum) and an absorptive portion (e.g.silicon). The absorptive portion can absorb about 80% of onepolarization of light, and thus about 40% of the total amount of light.Much of the heat from this absorbed light conducts to the reflectiveportion of the wire, which can melt, thus destroying the polarizer.Thus, it can be a consideration to improve the high temperaturedurability of selectively-absorptive polarizers.

Ribs or wires of polarizers, especially for polarization of visible orultraviolet light, can have small, delicate ribs with nanometer-sizedpitch, wire-width, and wire-height. Polarizers are used in systems (e.g.projectors, semiconductor inspection tools, etc.) that require highperformance. Small defects in the polarizer, such as collapsed ribs, cansignificantly degrade system performance (e.g. distorted image from aprojector). Therefore, it can be a consideration to protect the ribsfrom physical damage, such as by touching, and from excessive heat toavoid rib melting.

Manufacture of polarizers can be difficult and expensive due to smallsize of the ribs. Some materials are more difficult to pattern and etchthan other materials in the polarizer. Manufacturability and reducingmanufacturing cost can be considerations.

Optical properties can be improved by reducing surface roughness of asurface of thin films of the polarizer. Reducing such surface roughnesscan be a consideration of polarizer manufacture.

SUMMARY

It has been recognized that it would be advantageous to provide apolarizer with high contrast (e.g. Tp/Ts), with high percenttransmission of one polarization, that can endure a high temperature,and that is resistant to physical damage. It has also been recognizedthat it would be advantageous to improve manufacturability and reducemanufacturing cost of such polarizers. It has also been recognized thatit can be helpful to reduce surface roughness of a surface of thin filmsof the polarizer. The present invention is directed to various methodsof making polarizers that satisfy these needs. Each embodiment maysatisfy one, some, or all of these needs.

The method can comprise (i) applying an uncured imprintable layer on asubstrate; (ii) imprinting a pattern of polarization structures in theuncured imprintable layer, wherein a longitudinal dimension of some ofthe polarization structures extend in a first direction, a longitudinaldimension of other of the polarization structures extend in a seconddirection, the first direction and the second direction are parallel tothe first side of the substrate, and the first direction is a differentdirection from the second direction; and (iii) curing the uncuredimprintable layer into a solid cured printed layer.

In one embodiment, the uncured imprintable layer can be a liquid withsolid inorganic nanoparticles dispersed throughout a continuous phaseand the cured printed layer can include a solid, interconnecting networkof the inorganic nanoparticles. In another embodiment, the uncuredimprintable layer can be a colloidal suspension including a dispersedphase and a continuous phase and curing the uncured imprintable layercan include removing the continuous phase to form the solid curedprinted layer. In another embodiment, the uncured imprintable layer canbe a solution including molecules in a solvent, the solvent includingwater and an organic liquid, the molecules including metal atoms bondedto reactive groups, where each reactive-group is independently —Cl,—OR², —OCOR², or —N(R²)₂, and R² is an alkyl group; and curing caninclude reacting the molecules to form a solid of the metal atomsinterconnected with each other, defining the cured printed layer.

BRIEF DESCRIPTION OF THE DRAWINGS (Drawings Might Not be Drawn to Scale)

FIG. 1 is a step 10 in a method of making a polarizer, including aschematic, cross-sectional side-view of a polarization device 15 on asubstrate 11 and an overcoat layer 14 on a surface 15 _(s) of thepolarization device 15 farthest from the substrate 11, in accordancewith an embodiment of the present invention.

FIG. 2 is a schematic perspective-view of a polarizer 20 withpolarization structures 12, which can be an array of wires, on asubstrate 11, in accordance with an embodiment of the present invention.

FIG. 3 is a step 30 in a method of making a polarizer, which can followstep 10, including a schematic, cross-sectional side-view of an uncuredcover layer 34 on a surface 14 _(s) of the overcoat layer 14 farthestfrom the polarization device 15, in accordance with an embodiment of thepresent invention.

FIG. 4 is a step 40 in a method of making a polarizer, which can followstep 30, including a schematic, cross-sectional side-view of the uncuredcover layer 34 formed into a cured cover layer 44, in accordance with anembodiment of the present invention.

FIG. 5 is a step 50 in a method of making a polarizer, which can followstep 30, including a schematic, cross-sectional side-view of a secondsubstrate 11 _(b) on the uncured cover layer 34, in accordance with anembodiment of the present invention.

FIG. 6 is a step 60 in a method of making a polarizer, which can followstep 50, including a schematic, cross-sectional side-view of the uncuredcover layer 34 formed into a cured cover layer 44, in accordance with anembodiment of the present invention.

FIGS. 7-8 are steps 70 and 80 in a method of making a polarizer, whichcan follow step 30, including schematic, cross-sectional side-views ofimprinting a pattern of structures 84 in the uncured cover layer 34, inaccordance with an embodiment of the present invention.

FIG. 9 is a step 90 in a method of making a polarizer, which can followstep 80, including a schematic, cross-sectional side-view of the uncuredcover layer 34 formed into a cured cover layer 44, in accordance with anembodiment of the present invention.

FIG. 10a is a step 100 a in a method of making a polarizer, including aschematic, cross-sectional side-view of polarization structures 12 on asubstrate 11, in accordance with an embodiment of the present invention.

FIG. 10b is a schematic perspective-view of a polarizer 100 b includinga schematic, cross-sectional side-view of polarization structures 12 ona substrate 11, showing that the polarization structures 12 can comprisean array of wires, each wire including a reflective wire 102 and anabsorptive rib 101, in accordance with an embodiment of the presentinvention.

FIG. 11a is a step 110 in a method of making a polarizer, which canfollow step 100 a, including a schematic, cross-sectional side-view ofan uncured fill layer 134 on top of polarization structures 12 andextending into channels 13 between the polarization structures 12, inaccordance with an embodiment of the present invention.

FIG. 11b is a step 110 in a method of making a polarizer, which canfollow step 100 a, including a schematic, cross-sectional side-view ofan uncured fill layer 134 in channels 13 between the polarizationstructures 12, but not on top of the polarization structures 12, inaccordance with an embodiment of the present invention.

FIG. 12a is a step 120 a in a method of making a polarizer, which canfollow step 110 a, including a schematic, cross-sectional side-view ofthe uncured fill layer 134 formed into a cured fill layer 144, inaccordance with an embodiment of the present invention.

FIG. 12b is a step 120 b in a method of making a polarizer, which canfollow step 110 b, including a schematic, cross-sectional side-view ofthe uncured fill layer 134 formed into a cured fill layer 144, inaccordance with an embodiment of the present invention.

FIGS. 13-14 are steps 130 and 140 in a method of making a polarizer,which can follow step 110 a, including schematic, cross-sectionalside-views of imprinting a pattern of structures 84 in the uncured filllayer 134, in accordance with an embodiment of the present invention.

FIG. 15 is a step 150 in a method of making a polarizer, which canfollow step 140, including a schematic, cross-sectional side-view of theuncured fill layer 134 formed into a cured fill layer 144, in accordancewith an embodiment of the present invention.

FIG. 16 is a step 160 in a method of making a polarizer, which canfollow step 110 a, including a schematic, cross-sectional side-view of asecond substrate 11 b on the uncured fill layer 134, in accordance withan embodiment of the present invention.

FIG. 17 is a step 170 in a method of making a polarizer, which canfollow step 160, including a schematic, cross-sectional side-view of theuncured fill layer 134 formed into a cured fill layer 144, in accordancewith an embodiment of the present invention.

FIGS. 18-19 are steps 180 and 190 in a method of making a polarizer,including a schematic, cross-sectional side-view of an uncuredimprintable layer 184 on a substrate 11 and imprinting a pattern ofpolarization structures 12 in the uncured imprintable layer 184, inaccordance with an embodiment of the present invention.

FIG. 20 is a step 200 in a method of making a polarizer, which canfollow step 190, including a schematic, cross-sectional side-view of theuncured imprintable layer 184 formed into a cured printed layer 204, inaccordance with an embodiment of the present invention.

FIG. 21 is a schematic top-view of the polarizer of FIG. 19 or FIG. 20,in accordance with an embodiment of the present invention.

FIGS. 22 and 23 are steps 220 and 230 in a method of making a polarizer,and show a schematic, cross-sectional side-view of a polarization device15 located on a first side 11 _(f) of a substrate 11 and an uncuredbackside layer 234 on an opposite, second side 11 _(s), of the substrate11, and imprinting a pattern of structures 84 in the uncured backsidelayer 234, in accordance with an embodiment of the present invention.

FIG. 24 is a step 240 in a method of making a polarizer, which canfollow step 230, including a schematic, cross-sectional side-viewshowing the uncured backside layer 234 formed into a cured backsidelayer 244, in accordance with an embodiment of the present invention.

FIG. 25 is a step 250 in a method of making a polarizer, including aschematic, cross-sectional side-view showing applying an uncured lowerthin film 251 _(L) on a substrate 11, in accordance with an embodimentof the present invention.

FIG. 26 is a step 260 in a method of making a polarizer, which canfollow step 250, including a schematic, cross-sectional side-viewshowing curing the uncured lower thin film 251 _(L) into a cured lowerthin film 261, in accordance with an embodiment of the presentinvention.

FIG. 27 is a step 270 in a method of making a polarizer, which canfollow step 260, including a schematic, cross-sectional side-viewshowing applying a reflective thin film 272 on the cured lower thin film261, in accordance with an embodiment of the present invention.

FIG. 28a is a step 280 a in a method of making a polarizer, which canfollow step 270, including a schematic, cross-sectional side-viewshowing etching the reflective thin film 272 to form polarizationstructures 12, in accordance with an embodiment of the presentinvention.

FIG. 28b is a step 280 b in a method of making a polarizer, which canfollow step 270, including a schematic, cross-sectional side-viewshowing etching the reflective thin film 272 and the cured lower thinfilm 261 _(L) to form polarization structures 12, in accordance with anembodiment of the present invention.

FIG. 29 is a step 290 in a method of making a polarizer, which canfollow step 270, including a schematic, cross-sectional side-viewshowing applying an uncured upper thin film 251 _(U) on the reflectivethin film 272, in accordance with an embodiment of the presentinvention.

FIG. 30 is a step 300 in a method of making a polarizer, which canfollow step 290, including a schematic, cross-sectional side-viewshowing curing the uncured upper thin film 251 _(U) into a cured upperthin film 261 _(U), in accordance with an embodiment of the presentinvention.

FIG. 31 is a step 310 in a method of making a polarizer, which canfollow step 300, including a schematic, cross-sectional side-viewshowing etching the cured upper thin film 261 _(U) and the reflectivethin film 272 and to form polarization structures 12, in accordance withan embodiment of the present invention.

FIG. 32 is a step 320 in a method of making a polarizer, which canfollow step 300, including a schematic, cross-sectional side-viewshowing etching the cured upper thin film 261 _(U), the reflective thinfilm 272, and the cured lower thin film 261 _(L) and to formpolarization structures 12, in accordance with an embodiment of thepresent invention.

FIG. 33 is a step 330 in a method of making a polarizer, including aschematic, cross-sectional side-view showing applying a reflective thinfilm 272 on the substrate 11 and applying an uncured lower thin film 251_(L) on the reflective thin film 272, in accordance with an embodimentof the present invention.

FIG. 34 is a step 340 in a method of making a polarizer, which canfollow step 330, including a schematic, cross-sectional side-viewshowing curing the uncured upper thin film 251 _(U) into a cured upperthin film 261 _(U), in accordance with an embodiment of the presentinvention.

FIG. 35 is a step 350 in a method of making a polarizer, which canfollow step 340, including a schematic, cross-sectional side-viewshowing etching the cured upper thin film 261 _(U) and the reflectivethin film 272 and to form polarization structures 12, in accordance withan embodiment of the present invention.

FIG. 36 is a step 360 in a method of making a polarizer, includingimprinting separate pixels, in accordance with an embodiment of thepresent invention.

FIG. 37 is a step 370 in a method of making a polarizer, includingsputter deposition of a thin film 375 onto the uncured layer 374, inaccordance with an embodiment of the present invention.

FIG. 38 is a step 380 in a method of making a polarizer, includingsputter deposition of a thin film 375 onto the cured fill layer 384, inaccordance with an embodiment of the present invention.

DEFINITIONS

As used herein, the term “contrast” means a fraction of transmissionthrough the WGP of the predominantly transmitted polarization (e.g. Tp)divided by a fraction of transmission through the WGP of an oppositepolarization (e.g. Ts). For example, contrast=Tp/Ts.

As used herein, the term “longitudinal dimension” means a longestdimension of the polarization structures 12 parallel to the first side11 _(f) of the substrate 11.

As used herein, the term “metal atoms” includes both true metals as wellas metalloids, such as for example silicon and germanium.

As used herein, the term “nanometer-sized” means dimensions of ≤1000 nm.

As used herein, the term “nanoparticles” means particles with a width ordiameter of ≤1000 nm. The nanoparticles can have a width or diameter of≤500 nm, ≤100 nm, ≤50 nm, or ≤10 nm if explicitly so stated in theclaims. The aforementioned width or diameter can be a largest width ordiameter of all the nanoparticles if explicitly so stated in the claims.The nanoparticles can also have a width or diameter of ≥0.1 nm, ≥1 nm,or ≥5 nm if explicitly so stated in the claims. The aforementioned widthor diameter can be a smallest width or diameter of all the nanoparticlesif explicitly so stated in the claims.

As used herein, the term “nm” means nanometer(s) and the term “mm” meansmillimeter(s).

As used herein, the terms “on”, “located on”, “located at”, and “locatedover” mean located directly on or located over with some other solidmaterial between. The terms “located directly on”, “adjoin”, “adjoins”,and “adjoining” mean direct and immediate contact with no other solidmaterial between.

As used herein, the term “perpendicular” means exactly perpendicular orwithin 20 degrees of exactly perpendicular.

As used herein, the term “pixels” means different regions of an opticaldevice with intentionally different optical properties.

As used herein, the term “parallel” means exactly parallel, parallelwithin normal manufacturing tolerances, or nearly parallel, such thatany deviation from exactly parallel would have negligible effect forordinary use of the device.

As used herein, the term “rpm” means revolutions per minute.

Materials used in optical structures can absorb some light, reflect somelight, and transmit some light. The following definitions distinguishbetween materials that are primarily absorptive, primarily reflective,or primarily transparent. Each material can be considered to beabsorptive, reflective, or transparent in a specific wavelength range(e.g. ultraviolet, visible, or infrared spectrum) and can have adifferent property in a different wavelength range. Thus, whether amaterial is absorptive, reflective, or transparent is dependent on theintended wavelength range of use. Materials are divided into absorptive,reflective, and transparent based on reflectance R, the real part of therefractive index n, and the imaginary part of the refractiveindex/extinction coefficient k. Equation 1 is used to determine thereflectance R of the interface between air and a uniform slab of thematerial at normal incidence:

$\begin{matrix}{R = \frac{\left( {n - 1} \right)^{2} + k^{2}}{\left( {n + 1} \right)^{2} + k^{2}}} & {{Equation}\mspace{14mu} 1}\end{matrix}$

Unless explicitly specified otherwise herein, materials with k≤0.1 inthe specified wavelength range are “transparent” materials, materialswith k>0.1 and R≥5 0.6 in the specified wavelength range are“absorptive” materials, and materials with k>0.1 and R>0.6 in thespecified wavelength range are “reflective” materials.

DETAILED DESCRIPTION First Method—Cover Layer 34/44 on Overcoat Layer 14

As illustrated in FIGS. 1-9, a first method of making a polarizer cancomprise some or all of the following steps, which can be performed inthe following order. There may be additional steps not described below.These additional steps may be before, between, or after those described.

As illustrated in FIG. 1, one step 10 in the first method can includeproviding a polarization device 15 on a substrate 11. The substrate 11can be transparent. The polarization device 15 can include objects ormaterials arranged in a pattern for polarization of light. For example,the polarization device 15 can be an array of parallel wires as thepolarization structures 12 as shown in FIG. 2, polarization structures12 extending in different directions such as is shown in FIGS. 19-21, ora film polarizer.

An overcoat layer 14 can be applied or located on a surface 15 _(s) ofthe polarization device 15 farthest from the substrate 11. The overcoatlayer 14 can be a single layer of a single material or can be multiplelayers of different materials. The overcoat layer 14 can be sputteredonto the polarization device 15, applied by atomic layer deposition, orother method. The overcoat layer 14 can be applied as described inpatent publication US 2010/0103517.

If the polarization device 15 includes an array of wires with channels13 between adjacent wires, the overcoat layer 14 can extend into thechannels 13 and can fill the channels 13. Alternatively, the channels 13can be free of the overcoat layer 14. The channels 13 can be partiallyfilled with the overcoat layer 14, such as for example ≥10% filled, ≥25%filled, or ≥40% filled, and can be ≤60% filled, ≤80% filled, or ≤90%filled.

A schematic perspective-view of a polarizer 20 is illustrated in FIG. 2,with elongated wires on a substrate 11, in accordance with an embodimentof the present invention. The polarization structures 12 of the variousembodiments described herein can be similarly elongated. As used herein,the term “elongated” means that a length L₁₂ of the wires issubstantially greater than wire width W₁₂ or wire thickness Th₁₂ (e.g.L₁₂ can be ≥10 times, ≥100 times, ≥1000 times, or ≥10,000 times largerthan wire width W₁₂ and/or wire thickness Th₁₂). For example, L₁₂ can be≥1 mm or ≥10 mm, W₁₂ can be ≤200 nm or ≤100 nm, and Th₁₂ can be ≤500 nmor ≤1000 nm.

As illustrated in FIG. 3, another step 30 in the first method can beapplying an uncured cover layer 34 to an outer surface 14 _(s) of theovercoat layer 14 farthest from the polarization device 15. Step 30 canfollow step 10.

As illustrated in FIG. 5, the substrate 11 can be a first substrate 11_(a). The first method can further comprise step 50, placing a secondsubstrate 11 _(b) onto the uncured cover layer 34. Step 50 can followstep 30.

As illustrated in FIGS. 7-8, other steps 70 and 80 in the first methodcan include imprinting a pattern of structures 84 in the uncured coverlayer 34. A stamp 55 can imprint the structures 84 in the uncured coverlayer 34. The structures 84 can be sized and shaped to reduce reflectionof incident light, to increase heat transfer away from the polarizer, orboth. For example, the structures 84 can be shaped like ribs or pillarsto increase surface area for heat transfer, to reduce reflection, orboth. Steps 70 and 80 can follow step 30.

As illustrated in FIGS. 4, 6, and 9, steps 40, 60, and 90 respectivelyin the first method can include curing (i.e. causing a chemical reactionin) the uncured cover layer 34 to form a cured cover layer 44.Characteristics of the uncured cover layer 34, characteristics of thecured cover layer 44, and curing are described below in the AddedFeatures Applicable to All Methods section. Step 40 can follow step 30,step 60 can follow step 50, and step 90 can follow step 80.

If the polarization device 15 includes channels 13 between adjacentpolarization structures 12, it can be difficult to manufacture theovercoat layer 14 with sufficient integrity to keep the uncured coverlayer 34, and thus also the cured cover layer 44, out of the channels13. If the uncured cover layer 34 enters only some of the channels 13,tensile forces in the uncured cover layer 34, in the cured cover layer44, or both can cause polarization structures 12 to topple, thusimpairing polarization. Also, polarization will not be uniform acrossthe polarizer if the cured cover layer 44 is in only some of thechannels 13.

One way to keep the uncured cover layer 34 out of the channels 13 is toselect chemistry of the uncured cover layer 34 that is repellant withrespect to chemistry of all of, or at least the outer surface 14 _(s)of, the overcoat layer 14. A material for the overcoat layer 14 or forthe outer surface 14 _(s) of the overcoat layer 14 can have a relativelylow surface energy and a solvent of the uncured cover layer 34 can havea relatively high surface tension. The surface tension of the uncuredcover layer 34 can be greater than the surface energy of the outersurface 14 _(s) of the overcoat layer 14. For example, if the uncuredcover layer 34 includes water as a solvent, then the outer surface 14,of the overcoat layer 14 can include a hydrophobic coating. Another wayto keep the uncured cover layer 34 out of the channels 13 is to uselarger nanoparticles.

Proper selection of chemistry of the uncured cover layer 34 and of theouter surface 14 _(s) and large nanoparticle size, can result inchannels 13 between adjacent polarization structures 12 that are free ofthe uncured cover layer 34 and free of the cured cover layer 44, or thatare nearly free of the uncured cover layer 34 and the cured cover layer44. For example, ≥98%, ≥99%, or ≥99.9% of a total volume of the channels13 can be free of the uncured cover layer 34 and the cured cover layer44.

A polarizer made from the first method can have some or all of thefollowing characteristics: high contrast (e.g. Tp/Ts), ability to endurea high temperature, resistant to physical damage, and relatively easy tomanufacture.

Second Method—Fill Layer 134/144 in Channels 13

As illustrated in FIGS. 10a -17, a second method of making a polarizercan comprise some or all of the following steps, which can be performedin the following order. There may be additional steps not describedbelow. These additional steps may be before, between, or after thosedescribed.

As illustrated in FIG. 10a , one step 10 in the second method can beproviding a polarizer. The polarizer can include polarization structures12 on a substrate 11. The substrate 11 can be transparent. Thepolarization structures 12 can be arranged in a pattern for polarizationof light. For example, the polarization structures 12 can be an array ofparallel, elongated wires with channels 13 between adjacent wires.Alternately, the polarization structures 12 can extend in differentdirections as described below and shown in FIGS. 19-21. The polarizationstructures 12 can have a proximal end 12 _(p) closer to the substrate 11and a distal end 12 _(d) farther from the substrate 11. The polarizationstructures 12 can include materials for polarization of light.

As illustrated in FIG. 10b , polarizer 100 b is shown with thepolarization structures 12 comprising an array of wires, each wireincluding a reflective wire 102 and an absorptive rib 101. On polarizer100 b, the reflective wire 102 is sandwiched between the absorptive rib101 and the substrate 11. An opposite order, with the absorptive rib 101sandwiched between the reflective wire 102 and the substrate 11, iswithin the scope of the inventions herein. The polarization structures12 of any of the methods described herein can include a reflective wire102 and an absorptive rib 101, however, this embodiment might beparticularly suited to the second method if the cured cover layer 44 isused as a heat sink or for heat transfer of heat away from thepolarization structures 12.

As illustrated in FIG. 11a , another step 110 a in the second method canbe applying an uncured fill layer 134 on top of the polarizationstructures 12 and extending into channels 13 between the polarizationstructures 12. Step 110 a can follow step 100 a. Step 110 a can usepolarizer 100 b.

As illustrated in FIG. 11b , another step 110 b in the second method canbe applying an uncured fill layer 134 in channels 13 between thepolarization structures 12 but not on top of the polarization structures12. Step 110 b can follow step 100 a. Step 110 b can use polarizer 100b.

As illustrated in FIGS. 14-15, other steps 140 and 150 in the secondmethod can include imprinting a pattern of structures 84 in the uncuredfill layer 134. A stamp 55 can be used to imprint the structures 84. Thestructures 84 can be sized and shaped to reduce reflection of incidentlight, to increase heat transfer away from the polarizer, or both. Forexample, the structures 84 can be shaped like ribs or pillars toincrease surface area for heat transfer, to reduce reflection, or both.Steps 140 and 150 can follow step 110.

As illustrated in FIG. 16, the substrate 11 can be a first substrate 11_(a). The second method can further comprise step 160, placing a secondsubstrate 11 _(b) onto the uncured fill layer 134. Step 160 can followstep 110.

As illustrated in FIGS. 12a, 12b , 15, and 17, steps 120 a, 120 b, 150,and 170 respectively in the second method can include curing (i.e.causing a chemical reaction in) the uncured fill layer 134 to form acured fill layer 144. Characteristics of the uncured fill layer 134,characteristics of the cured fill layer 144, and curing are describedbelow in the Added Features Applicable to All Methods section. Step 120a can follow step 110 a, step 120 b can follow step 110 b, step 150 canfollow step 140, and step 170 can follow step 160.

In the second method, complete, or nearly complete, filling the channels13 with the cured fill layer 144 can be a consideration for opticalproperties of the polarizer and can be a consideration for structuralsupport of the polarization structures 12. For example, the cured filllayer 144 can fill ≥75%, ≥90%, ≥95%, or ≥98% of the channels 13.

Filling the channels with the uncured fill layer 134 facilitates fillingthe channels with the cured fill layer 144. One way to help fill thechannels 13 is to select chemistry of the uncured fill layer 134 that isattractive with respect to chemistry of an outer surface of thepolarization structures 12. For example, the uncured fill layer 134 canbe primarily an aqueous solution and the outer surface of thepolarization structures 12 can be hydrophilic, such as an oxide. Amaterial for the outer surface of the polarization structures 12 canhave a relatively high surface energy and a solvent of the uncured filllayer 134 can have a relatively low surface tension. The surface energyof the outer surface of the polarization structures 12 can be greaterthan the surface tension of the uncured fill layer 134. For example, thesurface energy of the surface of the polarization structures 12 can betwo times greater than, five times greater than, or ten times greaterthan the surface tension of the uncured fill layer 134. For example, ifthe uncured fill layer 134 includes water as a solvent, then the outersurface of the polarization structures 12 can include a hydrophiliccoating. Another way to help fill the channels 13 with the uncured filllayer 134 is to use smaller nanoparticles.

A polarizer made from the second method can have some or all of thefollowing characteristics: high contrast (e.g. Tp/Ts), ability to endurea high temperature, resistant to physical damage, and be relatively easyto manufacture. This embodiment can be particularly helpful for hightemperature endurance due to the cured fill layer 144 in the channels13—the cured fill layer 144 can be an effective heat sink or heattransfer path to draw heat away from the polarization structures 12.

Third Method—Imprintable Layer 184 and Printed Layer 204

As illustrated in FIGS. 18-21, a third method of making a polarizer cancomprise some or all of the following steps, which can be performed inthe following order. There may be additional steps not described below.These additional steps may be before, between, or after those described.

As illustrated in FIG. 18, one step 180 in the third method can includeproviding a substrate 11 that is transparent. An uncured imprintablelayer 184 can be applied to a first side 11 _(f) of the substrate 11. Asillustrated in FIGS. 18-19, steps 180 and 190 in the third method caninclude imprinting a pattern of polarization structures 12 in theuncured imprintable layer 184.

As illustrated in FIG. 20, another step 200 in the method can includecuring (i.e. causing a chemical reaction in) the uncured imprintablelayer 184 to form a cured printed layer 204. Characteristics of theuncured imprintable layer 184, characteristics of the cured printedlayer 204, and curing are described below in the Added FeaturesApplicable to All Methods section. Step 200 can follow step 190.

Characteristics of the polarization structures 12 are shown in FIGS.19-21 and can include the following: A longitudinal dimension L of someof the polarization structures 12 can extend in a first direction D₁. Alongitudinal dimension L of other of the polarization structures 12 canextend in a second direction D₂. The first direction D₁ and the seconddirection D₂ can be parallel to the first side 11 _(f) of the substrate11. The first direction D₁ can be a different direction from the seconddirection D₂. The first direction D₁ can be perpendicular to the seconddirection D₂. A longitudinal dimension L of some of the polarizationstructures 12 can extend in at least three different directions or atleast four different directions.

The polarization structures 12 can have a width W that is perpendicularto the longitudinal dimension L and parallel to the first side 11 _(f)of the substrate 11. The width W of at least some of the polarizationstructures 12 extending in the first direction D₁ and a width W of atleast some of the polarization structures 12 extending in the seconddirection D₂ can be ≤100 nm, ≤500 nm, or ≤1000 nm.

The polarization structures 12 can have multiple, different thicknessesTh. The thickness Th is a dimension perpendicular to the first side 11_(f) of the substrate 11. For example, the polarization structures canhave ≥two, ≥three, ≥four, or ≥five different thicknesses Th. Each ofthese different thicknesses Th can differ from each other, such as forexample by ≥5 nm, ≥10 nm, ≥20 nm, or ≥40 nm and/or by ≤60 nm, ≤120 nm,or ≤500 nm.

The substrate 11 and the polarization structures 12 can be made of thesame material. For example, the substrate 11 and the polarizationstructures 12 can both be dielectric. A material composition of thesubstrate 11 and of the polarization structures 12 can be or can includeglass.

One distinct characteristic of the polarizer of the third method is theability to transmit ≥50% of incident unpolarized light as a singlepolarization. For example, this polarizer can transmit ≥50%, ≥60%, ≥70%,or ≥80%, of incident light as a single polarization.

Examples of an extinction ratio of the polarizer of the third method canbe ≥2, ≥3, ≥5, or ≥10. The extinction ratio means an amount of incidentlight transmitted as a predominantly-transmitted polarization divided byan amount of the incident light transmitted as an opposite polarization.

A polarizer made from the third method can have a high percenttransmission of one polarization and can be relatively easy tomanufacture.

Fourth Method—Backside Layer 234/244

As illustrated in FIGS. 22-24, a fourth method of making a polarizer cancomprise some or all of the following steps, which can be performed inthe following order. There may be additional steps not described below.These additional steps may be before, between, or after those described.

As illustrated in FIG. 22, one step 220 in the fourth method can includeproviding a polarizer with a substrate 11 having a first side 11 _(f)and a second side 11 _(s) opposite of the first side 11 _(f). Thesubstrate 11 can be transparent. A polarization device 15 can be locatedon the first side 11_(f) of the substrate 11. The polarization device 15can include objects or materials arranged in a pattern for polarizationof light. The polarization device 15 can be any described herein orother type of polarizer.

As illustrated in FIGS. 22-23, steps 220 and 230 in the fourth methodcan include applying an uncured backside layer 234 to the second side 11_(s) of the substrate 11 and imprinting a pattern of structures 84 inthe uncured backside layer 234. A stamp 55 can be used to imprint thestructures 84. The structures 84 can be sized and shaped to reducereflection of incident light, to increase heat transfer away from thepolarizer, or both. For example, the structures 84 can be shaped likeribs or pillars to increase surface area for heat transfer, to reducereflection, or both.

As illustrated in FIG. 24, another step 240 in the fourth method caninclude curing (i.e. causing a chemical reaction in) the uncuredbackside layer 234 to form a cured backside layer 244. Characteristicsof the uncured backside layer 234, characteristics of the cured backsidelayer 244, and curing are described below in the Added FeaturesApplicable to All Methods section. Step 240 can follow step 230.

A polarizer made from the fourth method can have some or all of thefollowing characteristics: a high percent transmission of onepolarization, ability to endure a high temperature due to the imprintedstructures 84, and relatively easy to manufacture.

Fifth Method—Thin Films 251/261

As illustrated in FIGS. 25-35, a fifth method of making a polarizer cancomprise some or all of the following steps, which can be performed inthe following order. There may be additional steps not described below.These additional steps may be before, between, or after those described.

As illustrated in FIGS. 25, 29, and 33, the method can comprise applyingan uncured thin film 251 on a substrate 11. As illustrated in FIGS. 26,30, and 34, another step in the fifth method can include curing (i.e.causing a chemical reaction in) the uncured thin film 251 to form acured thin film 261. Characteristics of the uncured thin film 251,characteristics of the cured thin film 261, and curing are describedbelow in the Added Features Applicable to All Methods section.

As illustrated in FIGS. 27 and 33, the method can further compriseapplying a reflective thin film 272 on the substrate 11. As illustratedin FIGS. 28a, 28b , 31, 32, and 35, the method can also include etchingthe reflective thin film, and also etching the cured thin film(s) 261 insome embodiments, to form polarization structures 12.

As illustrated in FIG. 25, the uncured thin film 251 can be a loweruncured thin film 251 _(L) applied on the substrate 11 before applyingthe reflective thin film 272. As illustrated in FIG. 26, the loweruncured thin film 251 _(L) can be cured to form a lower cured thin film261. As illustrated in FIG. 27, the reflective thin film 272 can beapplied on the lower cured thin film 261. As illustrated in FIG. 28a ,the reflective thin film 272 can be etched to form polarizationstructures 12, which can consist of reflective thin film polarizationstructures 282.

As illustrated in FIG. 28b , the lower cured thin film 261 _(L) and thereflective thin film 272 can be etched to form polarization structures12 including reflective thin film polarization structures 282 and lowercured thin film polarization structures 281 _(L). The lower cured thinfilm polarization structures 281 _(L) can be sandwiched between thereflective thin film polarization structures 282 and the substrate 11.Each lower cured thin film polarization structure 281 _(L) can bealigned with a corresponding reflective thin film polarization structure282.

As illustrated in FIG. 29, step 290 can follow step 270, and an upperuncured thin film 251 _(U) can be applied on the reflective thin film272. As illustrated in FIG. 30, the upper uncured thin film 251 _(U) canbe cured to form an upper cured thin film 261 _(U). As illustrated inFIG. 31, the upper cured thin film 261 _(U) and the reflective thin film272 can be etched to form polarization structures 12 including uppercured thin film polarization structures 281 _(U) and reflective thinfilm polarization structures 282. As illustrated in FIG. 32, the uppercured thin film 261 _(U), the reflective thin film 272, and the lowercured thin film 261 _(L) can be etched to form polarization structures12 including upper cured thin film polarization structures 281 _(U),reflective thin film polarization structures 282, and lower cured thinfilm polarization structures 281 _(L). The reflective thin filmpolarization structures 282 can be sandwiched between the upper curedthin film polarization structures 281 _(U) and the lower cured thin filmpolarization structures 281 _(L). Each lower cured thin filmpolarization structure 281 _(L), reflective thin film polarizationstructure 282, and upper cured thin film polarization structure 281 _(U)can be aligned together.

As illustrated in FIG. 33, the uncured thin film 251 can be an upperuncured thin film 251 _(U) and the reflective thin film 272 can beapplied on the substrate 11 before applying the upper uncured thin film251 _(U). As illustrated in FIG. 34, the upper uncured thin film 251_(U) can be cured to form an upper cured thin film 261 _(U). Asillustrated in FIG. 35, the upper cured thin film 261 _(U) and thereflective thin film 272 can be etched to form polarization structures12 including upper cured thin film polarization structures 281 _(U) andreflective thin film polarization structures 282. The reflective thinfilm polarization structures 282 can be sandwiched between the uppercured thin film polarization structures 281 _(U) and the substrate 11.Each upper cured thin film polarization structure 281 _(U) can bealigned with a corresponding reflective thin film polarization structure282.

Added Features Applicable to All Methods

In the following discussion, the uncured cover layer 34, the uncuredfill layer 134, the uncured imprintable layer 184, the uncured backsidelayer 234, the uncured thin film(s) 251 will be referred to as anuncured layer. In the following discussion, the cured cover layer 44,the cured fill layer 144, the cured printed layer 204, the curedbackside layer 244, and the cured thin film(s) 261 will be referred toas a cured layer.

In one aspect, the uncured layer can be a liquid with solid inorganicnanoparticles dispersed throughout a continuous phase. Curing, orcausing a chemical reaction in, the uncured layer can include formingthe uncured layer into a solid, interconnecting network of the inorganicnanoparticles, defining a cured layer.

In another aspect, the uncured layer can be a colloidal suspensionincluding a dispersed phase and a continuous phase. Curing, or causing achemical reaction in, the colloidal suspension can include removing thecontinuous phase to form a solid, defining the cured layer. The solidcan be inorganic.

The inorganic nanoparticles, the dispersed phase, or both can includesome metal atoms bonded to organic moieties. In one aspect, each metalatom can be bonded to no more than one organic moiety. Examples of theorganic moieties include —CH₃ and —CH₂CH₃. Consequently, the cured layercan include embedded organic moieties. These embedded organic moietiescan be useful for changing properties of the cured layer, such aschanging its optical properties and hardness.

In another embodiment, the uncured layer can be a solution includingmolecules in a solvent. The solvent can include water and an organicliquid. The molecules can include metal atoms bonded to reactive groupsR¹. Each reactive-group can be, independently, —Cl, —OR², —OCOR², or—N(R²)₂, where R² is an alkyl group. The alkyl group has at least onecarbon atom, but can be small, such as for example with ≤2 carbon atoms,≤3 carbon atoms, ≤5 carbon atoms, or ≤10 carbon atoms. For example, thealkyl group can be —CH₃ or —CH₂CH₃. The solid inorganic nanoparticlesreferred to above can include the metal atoms described in thisparagraph.

In certain embodiments, all bonds, or all except one of the bonds, ofeach of the metal atoms, can be to these reactive groups. For example,these molecules can be (CH₃)Si(R¹)₃, Si(R¹)₄, Al(R¹)₃, (CH₃)Al(R¹)₂,(CH₃)Ti(R¹)₃, Ti(R¹)₄, or combinations thereof. Curing, or causing achemical reaction in, the solution can include reacting the molecules toform a solid, defining the cured layer, with the metal atomsinterconnected with each other. The solid can be inorganic. In oneembodiment, the molecules can have a relatively small molecular weight,such as for example ≥70 g/mol, ≥80 g/mol, ≥90 g/mol, ≥100 g/mol, or ≥110g/mol and ≤125 g/mol, ≤150 g/mol, ≤175 g/mol, or ≤200 g/mol.

Forming the uncured layer into the cured layer can include evaporationof at least some liquid. In one embodiment, all liquid initially in theuncured layer either reacts to form a solid (the cured layer) or isevaporated. Forming the uncured layer into the cured layer can includeuse of ultraviolet light, heat or both. Integrity of the cured layer canbe improved by curing at a relatively low temperature, such as forexample ≥30° C., ≥50° C., or ≥100° C. and ≤150° C., ≤200° C., ≤250° C.,or ≤300° C.

The uncured layer, the cured layer, or both can have a low index ofrefraction for improved optical performance. This can be particularlybeneficial for embodiments with cured layer in the channels 13 betweenthe polarization structures 12. For example, the index of refraction ofuncured layer, the cured layer, or both can be ≤1.1, ≤1.2, ≤1.3, or≤1.4. In one embodiment, the index of refraction of uncured layer, thecured layer, or both can be ≥1.0.

One way of achieving this low index of refraction is to include smallvoids or cavities in the cured layer. These small voids, filled withair, lower the overall index of refraction of the cured layer. Forexample, the cured layer can include silicon dioxide, with an index ofrefraction of around 1.4-1.5, but with the voids, the overall index ofrefraction can be <1.4. These voids can be formed by use of a solvent inthe uncured layer which has larger molecules. For example, a solvent inthe uncured layer can have a molecular weight of ≥70 g/mol, ≥80 g/mol,≥90 g/mol, ≥100 g/mol, or ≥110 g/mol. As another example, a chemical inthis solvent can have a large number of atoms, such as for example ≥15atoms, ≥20 atoms, or ≥25 atoms. It can be a consideration for thissolvent to not have too high of a molecular weight so that it can besufficiently volatile. Therefore, this solvent can have a molecularweight of ≤125 g/mol, ≤150 g/mol, ≤175 g/mol, ≤200 g/mol, or ≤300 g/mol.This solvent can also have ≤30 atoms, ≤50 atoms, or ≤75 atoms. Further,this solvent can have a structure which occupies larger space, such asan aryl molecule or otherwise a molecule with double bonds. For example,the uncured layer can include benzene or xylene.

The inorganic nanoparticles, solid resulting from removing thecontinuous phase, and the metal atoms noted above can comprise aluminum,titanium, silicon, germanium, tin, lead, zirconium, or combinationsthereof. The cured layer can include aluminum oxide, titanium oxide,silicon oxide, germanium oxide, tin oxide, lead oxide, zirconium oxide,or combinations thereof. Aluminum oxide can be particularly useful if amajor function of the cured layer is heat transfer away from thepolarization structures 12. Silicon dioxide can be particularly usefuldue to its low index of refraction. Titanium dioxide can be particularlyuseful due to its high index of refraction.

The inorganic nanoparticles can be sized for keeping them out of thechannels 13. For example ≥90%, ≥95%, or ≥99% of the inorganicnanoparticles can have a diameter of ≥1 nm, ≥10 nm, or ≥50 nm.Alternatively, the inorganic nanoparticles can be sized for optimalfilling the channels 13. For example ≥90%, ≥95%, or ≥99% of theinorganic nanoparticles can have a diameter of ≤2 nm, ≤1 nm, or ≤0.5 nm.

As illustrated in FIGS. 7-9, 13-15, 18-20, and 22-24, and as describedabove, the method can include imprinting a pattern of structures. Asillustrated in FIG. 36, such imprinting can also include step 360,imprinting separate pixels. Although FIG. 36 shows different pixels withdifferent wire direction with respect to each other, the pixels candiffer in other ways with respect to each other.

As illustrated in FIGS. 37-38, any of the methods above can furthercomprise sputter deposition of a thin film 375 onto the uncured layer,the cured layer, or both, represented by reference numbers 374 and 384,respectively. The thin film 375 can be any material with desired opticalproperties, properties for protection of the polarizer, or both. Thethin film 265 can be a dielectric. Sputter deposition of the thin film375 can reduce voids in the uncured layer 374, the cured layer 384, orboth; therefore this sputter deposition step is particularly useful forembodiments in which it is desirable for the uncured layer 374 and thecured layer 384 to fill the channels 13.

The following can be used to improve applying the uncured layer, andforming the uncured layer into the cured layer, in any of the methodsdescribed above. The following steps can be performed in the followingorder: spin coating an uncured layer onto the polarization device orsubstrate 11, defining a first spin coat; baking the polarizer or coatedsubstrate 11, defining a first bake; spin coating an uncured layer ontothe first spin coat, defining a second spin coat; then baking thepolarizer or coated substrate 11, defining a second bake. The spincoating and baking steps can be repeated a third time, a fourth time, ormore times. Uniformity of cured layer can be improved by multiplerepeats of these spin coating and baking steps, but cost also increaseswith each repeat. Therefore, uniformity specifications can be weighedagainst cost in deciding the number of repeats, if any.

Time of each spin coat depends on desired thickness and on the spincoater. Example times include ≥2 seconds, ≥4 seconds, or ≥6 seconds and≤10 seconds, ≤20 seconds, or ≤30 seconds for each spin coat.

Examples of speed of the first spin coat, the second spin coat, oradditional spin coatings include ≥100 rpm, ≥500 rpm, ≥1000 rpm, or ≥1500rpm and ≤2500 rpm, ≤3000 rpm, ≤4000 rpm, or ≤8000 rpm. Examples oftemperature of the first bake, the second bake, or other bakes include≥30° C., ≥50° C., ≥100° C., or ≤150° C. and ≤250° C., ≤300° C., or ≤400°C.

The uncured layer, the cured layer, or both can be relatively thick bythe chemistry and methods of application described herein. For example,an average thickness Th of the layer, minimum thickness Th_(min) of thelayer, maximum thickness Th_(max) of the layer can have the followingvalues as specified in the claims: ≥10 nm, ≥50 nm, ≥100 nm, ≥200 nm and≤300 nm, ≤600 nm, or ≤1000 nm.

The methods can be combined. For example, the overcoat layer 14 and thecured cover layer 44 can be applied on the polarizers shown in FIG. 10a-15 or 18-35 and as described above. The cured fill layer 144 can beformed on top of the polarization structures 12 and extending intochannels 13 between the polarization structures 12 shown in FIGS. 18-21and 25-35 and as described above. The cured backside layer 244 can beformed on the second side 11 _(s) of the substrate 11 of any of thepolarizers described herein, as shown in FIGS. 22-24 and as describedabove. The cured thin film(s) 251, the cured thin film polarizationstructures 281, or both can be used with the any of the polarizers shownin the figures and described herein.

What is claimed is:
 1. A method of making a polarizer, the methodcomprising: providing a substrate that is transparent; applying anuncured imprintable layer on a first side of the substrate, the uncuredimprintable layer being a liquid with solid inorganic nanoparticlesdispersed throughout a continuous phase; imprinting a pattern ofpolarization structures in the uncured imprintable layer; wherein alongitudinal dimension of some of the polarization structures extend ina first direction, a longitudinal dimension of other of the polarizationstructures extend in a second direction, the first direction and thesecond direction are parallel to the first side of the substrate, andthe first direction is a different direction from the second direction;and curing the uncured imprintable layer into a cured printed layer, thecured printed layer including a solid, interconnecting network of theinorganic nanoparticles.
 2. The method of claim 1, wherein a width of atleast some of the polarization structures extending in the firstdirection and a width of at least some of the polarization structuresextending in the second direction is ≤500 nm, the width beingperpendicular to the longitudinal dimension and parallel to the firstside of the substrate.
 3. The method of claim 1, wherein the substrateand the polarization structures are dielectric.
 4. The method of claim1, wherein the first direction is perpendicular to the second direction.5. The method of claim 1, wherein the polarization structures have≥threedifferent thicknesses, the thicknesses being a dimension perpendicularto the first side of the substrate.
 6. The method of claim 1, whereinthe substrate has a second side opposite of the first side, the methodfurther comprising: applying an uncured backside layer to the secondside of the substrate, the uncured backside layer being a liquid withsolid inorganic nanoparticles dispersed throughout a continuous phase;and curing the uncured backside layer to form a cured backside layer,the cured backside layer including a solid, interconnecting network ofthe inorganic nanoparticles.
 7. The method of claim 1, furthercomprising: applying an uncured fill layer on top of the polarizationstructures and extending into channels between the polarizationstructures, the uncured fill layer being a liquid with solid inorganicnanoparticles dispersed throughout a continuous phase, chemistry of theuncured fill layer and chemistry of a surface of the polarizationstructures are attractive to each other; and curing the uncured filllayer to form a cured fill layer, the cured fill layer including asolid, interconnecting network of the inorganic nanoparticles.
 8. Themethod of claim 1, further comprising: applying an overcoat layer on thecured printed layer; applying an uncured cover layer to an outer surfaceof the overcoat layer farthest from the substrate, the uncured coverlayer being a liquid with solid inorganic nanoparticles dispersedthroughout a continuous phase, chemistry of the uncured cover layer andchemistry of the outer surface of the overcoat layer are repellant withrespect to each other; and curing the uncured cover layer to form acured cover layer, the cured cover layer including a solid,interconnecting network of the inorganic nanoparticles.
 9. The method ofclaim 1, wherein: the solid inorganic nanoparticles include metal atomsbonded to reactive groups, where each reactive-group is independently—Cl, —OR², —OCOR², or —N(R²)₂, and R² is an alkyl group; and curingincludes reacting the molecules to form a solid of the metal atomsinterconnected with each other as the solid, interconnecting network ofthe inorganic nanoparticles.
 10. A method of making a polarizer, themethod comprising: providing a substrate that is transparent; applyingan uncured imprintable layer to a first side of the substrate, theuncured imprintable layer being a colloidal suspension including adispersed phase and a continuous phase; imprinting a pattern ofpolarization structures in the uncured imprintable layer; wherein alongitudinal dimension of some of the polarization structures extend ina first direction, a longitudinal dimension of other of the polarizationstructures extend in a second direction, the first direction and thesecond direction are parallel to the first side of the substrate, andthe first direction is a different direction from the second direction;and curing the uncured imprintable layer by removing the continuousphase to form a solid, defining a cured printed layer.
 11. The method ofclaim 10, wherein imprinting the pattern of polarization structuresincludes imprinting separate pixels.
 12. The method of claim 10, furthercomprising: applying an uncured fill layer on top of the polarizationstructures and extending into channels between the polarizationstructures, the uncured fill layer being a colloidal suspensionincluding a dispersed phase and a continuous phase, chemistry of theuncured fill layer and chemistry of a surface of the polarizationstructures are attractive to each other and surface energy of thesurface of the polarization structures is greater than a surface tensionof the uncured fill layer; and curing the uncured fill layer by removingthe continuous phase to form a solid, defining a cured fill layer. 13.The method of claim 10, further comprising: applying an overcoat layeron the cured printed layer; applying an uncured cover layer to an outersurface of the overcoat layer farthest from the polarization device, theuncured cover layer being a colloidal suspension including a dispersedphase and a continuous phase; placing a second substrate onto theuncured cover layer; and curing the uncured cover layer by removing thecontinuous phase to form a solid, defining a cured cover layer.
 14. Amethod of making a polarizer, the method comprising: providing asubstrate that is transparent; applying an uncured imprintable layer toa first side of the substrate, the uncured imprintable layer being asolution including molecules in a solvent, the solvent including waterand an organic liquid, the molecules including metal atoms bonded toreactive groups, where each reactive-group is independently —Cl, —OR²,—OCOR², or —N(R²)₂, and R² is an alkyl group; imprinting a pattern ofpolarization structures in the uncured imprintable layer; wherein alongitudinal dimension of some of the polarization structures extend ina first direction, a longitudinal dimension of other of the polarizationstructures extend in a second direction, the first direction and thesecond direction are parallel to the first side of the substrate, andthe first direction is a different direction from the second direction;and reacting the molecules to form a solid of the metal atomsinterconnected with each other, defining a cured printed layer.
 15. Themethod of claim 14, further comprising: applying an uncured fill layeron top of the polarization structures and extending into channelsbetween the polarization structures, the uncured fill layer being asolution including molecules in a solvent, the solvent including waterand an organic liquid, the molecules including metal atoms bonded toreactive groups, where each reactive-group is independently —Cl, —OR²,—OCOR², or —N(R²)₂, and R² is an alkyl group, chemistry of the uncuredfill layer and chemistry of a surface of the polarization structures areattractive to each other; and reacting the molecules to form a solid ofthe metal atoms interconnected with each other, defining a cured filllayer.
 16. The method of claim 15, further comprising placing a secondsubstrate on the uncured fill layer.
 17. The method of claim 14, whereinevery bond of the metal atoms is bonded, independently, to one thereactive groups.
 18. The method of claim 14, wherein the metal atomsinclude Si(R¹)₄, Al(R¹)₃, Ti(R¹)₄, or combinations thereof, where eachR¹ is, independently, one of the reactive groups.
 19. The method ofclaim 14, wherein the molecules have a molecular weight of ≥≥80 g/moland ≤150 g/mol.
 20. The method of claim 14, wherein imprinting thepattern of polarization structures includes imprinting separate pixels.